LYMAN Primer Pocket Reamer 7777785/7777784 – Large/Small

.br-product-v3{--br-ink:#17201c;--br-muted:#54615b;--br-line:#d9e0dc;--br-soft:#f5f7f5;--br-deep:#10271d;--br-gold:#f2d58e;color:var(--br-ink);font:400 16px/1.65 system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;max-width:1100px;margin:0 auto;overflow-wrap:anywhere}
.br-product-v3 *{box-sizing:border-box}.br-product-v3 .br-hero-v3{background:var(--br-deep);color:#fff;padding:34px;border-radius:18px;margin:0 0 22px}.br-product-v3 .br-eyebrow{margin:0 0 8px;color:var(--br-gold);font-size:12px;font-weight:800;letter-spacing:.12em;text-transform:uppercase}.br-product-v3 .br-display{margin:0 0 12px;font-size:clamp(27px,4vw,44px);line-height:1.08;font-weight:850}.br-product-v3 .br-lead{margin:0;color:#e8eeea;max-width:850px}.br-product-v3 .br-pill{display:inline-block;margin-top:18px;padding:9px 14px;border-radius:999px;background:var(--br-gold);color:var(--br-deep);font-weight:800}.br-product-v3 .br-section{margin:26px 0}.br-product-v3 .br-section-title{margin:0 0 12px;font-size:22px;line-height:1.2;font-weight:850;color:var(--br-deep)}.br-product-v3 .br-box{border:1px solid var(--br-line);background:var(--br-soft);padding:18px;border-radius:14px}.br-product-v3 .br-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.br-product-v3 .br-card{border:1px solid var(--br-line);background:#fff;padding:18px;border-radius:14px}.br-product-v3 .br-card strong{display:block;color:var(--br-deep);margin-bottom:6px}.br-product-v3 ul,.br-product-v3 ol{margin:8px 0 0;padding-left:21px}.br-product-v3 li+li{margin-top:6px}.br-product-v3 .br-limit{border-left:5px solid var(--br-gold);background:#fffaf0}.br-product-v3 .br-tech{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.br-product-v3 .br-tech div{border-bottom:1px solid var(--br-line);padding:10px 0}.br-product-v3 .br-tech b{display:block;color:var(--br-deep)}.br-product-v3 details{border:1px solid var(--br-line);border-radius:12px;padding:12px 15px;background:#fff}.br-product-v3 details+details{margin-top:9px}.br-product-v3 summary{cursor:pointer;font-weight:800;color:var(--br-deep)}.br-product-v3 details p{margin:9px 0 0}.br-product-v3 .br-final{background:var(--br-deep);color:#fff;padding:24px;border-radius:16px}.br-product-v3 .br-final strong{color:var(--br-gold)}.br-product-v3 p{margin:0 0 10px}
@media(max-width:720px){.br-product-v3 .br-grid,.br-product-v3 .br-tech{grid-template-columns:1fr}.br-product-v3 .br-hero-v3{padding:24px 19px;border-radius:14px}.br-product-v3 .br-display{font-size:30px}.br-product-v3{overflow:hidden}}

LYMAN · Primer Pocket Tool · Large or Small
Remove military crimps in a controlled way – matching the primer pocket size
The Lyman Primer-Pocket-Reamer works on the crimped or burr edge of a primer pocket. Large and Small are separate versions; choosing the right one is crucial for purchase.
Check variant before buying
Black-Raptor purchase check
The tool is designed for cases whose primer pocket entrance is obstructed by a crimp or burr, preventing the seating of a new primer. It removes material and therefore requires much more caution than a simple cleaning tool.


Fits well
for reloadable cases with military primer crimps;
when Large or Small primer pocket is clearly identified;
for controlled small series with visual and tactile inspection.



Fits less well
if only powder residues are to be cleaned;
with unknown primer pocket size or damaged cases;
if fully automated processing is expected.



What the product practically brings you


Remove crimp The cutting geometry carefully removes the disturbing edge at the primer pocket entrance.


Improve seating feel A properly processed entrance makes it easier to seat the correct primer straight.


Two clear sizes Large and Small prevent the typical compromise of an unsuitable universal tool.


Limits, Na
Spare parts and avoid bad purchases
Too deep or crooked reaming can ruin the primer pocket. The tool does not calibrate either the depth or diameter of the entire primer pocket and does not repair stretched pockets. Only process reloadable, tested cases.
Technical data with practical consequences


Variants Large MPN 7777785 or Small MPN 7777784; not interchangeable

Function Crimp and burr removal at the primer pocket entrance; material removing

GTIN Large 011516777850 / Small 011516777843

Practical consequence easier, straighter positioning – only with moderate processing

Scope of delivery
One Lyman Primer-Pocket-Reamer in the chosen size Large or Small. Cases, primers, holder, drive and other case processing tools are not included.
Application, care and safety


Case decap, clean and check for reloadability.
Clearly determine primer pocket size.
Position reamer straight and work with little pressure.
Remove only as much material as needed for a clean entrance.
Remove chips and check result before seating the primer.

Wear safety glasses; never work on a case with a seated primer.

Frequently asked questions
Do I need Large or Small? That depends on the specific case. Do not rely solely on the caliber name, but check the primer specification. Does the tool clean the primer pocket? Its main purpose is material removal at crimped or burry entrance, not normal cleaning. Can I drive it motorized? Only if the manufacturer and the used chuck explicitly allow this. High speed increases the risk of excessive material removal.
BR classification: A useful special tool for crimped cases – provided size and processing depth are consciously controlled.